4 * Copyright (c) 2002-2005 Volkswagen Group Electronic Research
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions, the following disclaimer and
12 * the referenced file 'COPYING'.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of Volkswagen nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * Alternatively, provided that this notice is retained in full, this
21 * software may be distributed under the terms of the GNU General
22 * Public License ("GPL") version 2 as distributed in the 'COPYING'
23 * file from the main directory of the linux kernel source.
25 * The provided data structures and external interfaces from this code
26 * are not restricted to be used by modules with a GPL compatible license.
28 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
29 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
30 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
31 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
32 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
33 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
34 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
38 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
41 * Send feedback to <socketcan-users@lists.berlios.de>
45 #include <linux/config.h>
46 #include <linux/module.h>
47 #include <linux/version.h>
48 #include <linux/slab.h>
49 #include <linux/kmod.h>
50 #include <linux/init.h>
51 #include <linux/list.h>
52 #include <linux/spinlock.h>
53 #include <linux/rcupdate.h>
54 #include <linux/socket.h>
55 #include <linux/skbuff.h>
56 #include <linux/net.h>
57 #include <linux/netdevice.h>
59 #include <asm/uaccess.h>
61 #include <linux/can/af_can.h>
62 #include <linux/can/version.h>
67 #define NAME "Volkswagen AG - Low Level CAN Framework (LLCF)"
68 #define IDENT "af_can"
69 static __initdata const char banner[] = BANNER(NAME);
71 MODULE_DESCRIPTION(NAME);
72 MODULE_LICENSE("Dual BSD/GPL");
73 MODULE_AUTHOR("Urs Thuermann <urs.thuermann@volkswagen.de>, "
74 "Oliver Hartkopp <oliver.hartkopp@volkswagen.de>");
76 int stats_timer = 1; /* default: on */
77 module_param(stats_timer, int, S_IRUGO);
79 #ifdef CONFIG_CAN_DEBUG_CORE
81 module_param(debug, int, S_IRUGO);
82 #define DBG(args...) (debug & 1 ? \
83 (printk(KERN_DEBUG "CAN %s: ", __func__), \
85 #define DBG_FRAME(args...) (debug & 2 ? can_debug_cframe(args) : 0)
86 #define DBG_SKB(skb) (debug & 4 ? can_debug_skb(skb) : 0)
89 #define DBG_FRAME(args...)
93 static __init int can_init(void);
94 static __exit void can_exit(void);
96 static int can_create(struct socket *sock, int protocol);
97 static int can_notifier(struct notifier_block *nb,
98 unsigned long msg, void *data);
99 static int can_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg);
100 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,14)
101 static int can_rcv(struct sk_buff *skb, struct net_device *dev,
102 struct packet_type *pt, struct net_device *orig_dev);
104 static int can_rcv(struct sk_buff *skb, struct net_device *dev,
105 struct packet_type *pt);
107 static int can_rcv_filter(struct dev_rcv_lists *d, struct sk_buff *skb);
108 static struct dev_rcv_lists *find_dev_rcv_lists(struct net_device *dev);
109 static struct hlist_head *find_rcv_list(canid_t *can_id, canid_t *mask,
110 struct dev_rcv_lists *d);
111 static void can_rcv_lists_delete(struct rcu_head *rp);
112 static void can_rx_delete(struct rcu_head *rp);
113 static void can_rx_delete_all(struct hlist_head *rl);
117 struct list_head list;
118 struct net_device *dev;
119 void (*func)(unsigned long msg, void *data);
123 static LIST_HEAD(notifier_list);
124 static rwlock_t notifier_lock = RW_LOCK_UNLOCKED;
126 HLIST_HEAD(rx_dev_list);
127 struct dev_rcv_lists rx_alldev_list;
128 static spinlock_t rcv_lists_lock = SPIN_LOCK_UNLOCKED;
130 static kmem_cache_t *rcv_cache;
132 static struct packet_type can_packet = {
133 .type = __constant_htons(ETH_P_CAN),
138 static struct net_proto_family can_family_ops = {
140 .create = can_create,
141 .owner = THIS_MODULE,
144 /* notifier block for netdevice event */
145 static struct notifier_block can_netdev_notifier = {
146 .notifier_call = can_notifier,
149 /* table of registered CAN protocols */
150 static struct can_proto *proto_tab[CAN_NPROTO];
152 extern struct timer_list stattimer; /* timer for statistics update */
153 extern struct s_stats stats; /* packet statistics */
154 extern struct s_pstats pstats; /* receive list statistics */
156 module_init(can_init);
157 module_exit(can_exit);
159 /**************************************************/
160 /* af_can module init/exit functions */
161 /**************************************************/
163 static __init int can_init(void)
167 rcv_cache = kmem_cache_create("can_receiver", sizeof(struct receiver),
173 /* statistics init */
174 init_timer(&stattimer);
180 /* protocol register */
181 sock_register(&can_family_ops);
182 register_netdevice_notifier(&can_netdev_notifier);
183 dev_add_pack(&can_packet);
188 static __exit void can_exit(void)
191 /* stop statistics timer */
192 del_timer(&stattimer);
198 /* protocol unregister */
199 dev_remove_pack(&can_packet);
200 unregister_netdevice_notifier(&can_netdev_notifier);
201 sock_unregister(PF_CAN);
203 kmem_cache_destroy(rcv_cache);
206 /**************************************************/
207 /* af_can protocol functions */
208 /**************************************************/
210 void can_proto_register(struct can_proto *cp)
212 int proto = cp->protocol;
213 if (proto < 0 || proto >= CAN_NPROTO) {
214 printk(KERN_ERR "CAN: protocol number %d out of range\n", proto);
217 if (proto_tab[proto]) {
218 printk(KERN_ERR "CAN: protocol %d already registered\n", proto);
222 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,13)
223 if (proto_register(cp->prot, 0) != 0) {
227 proto_tab[proto] = cp;
229 /* use our generic ioctl function if the module doesn't bring its own */
231 cp->ops->ioctl = can_ioctl;
234 void can_proto_unregister(struct can_proto *cp)
236 int proto = cp->protocol;
237 if (!proto_tab[proto]) {
238 printk(KERN_ERR "CAN: protocol %d is not registered\n", proto);
241 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,13)
242 proto_unregister(cp->prot);
244 proto_tab[proto] = NULL;
247 void can_dev_register(struct net_device *dev,
248 void (*func)(unsigned long msg, void *), void *data)
252 DBG("called for %s\n", dev->name);
254 if (!(n = kmalloc(sizeof(*n), GFP_KERNEL)))
261 write_lock(¬ifier_lock);
262 list_add(&n->list, ¬ifier_list);
263 write_unlock(¬ifier_lock);
266 void can_dev_unregister(struct net_device *dev,
267 void (*func)(unsigned long msg, void *), void *data)
269 struct notifier *n, *next;
271 DBG("called for %s\n", dev->name);
273 write_lock(¬ifier_lock);
274 list_for_each_entry_safe(n, next, ¬ifier_list, list) {
275 if (n->dev == dev && n->func == func && n->data == data) {
281 write_unlock(¬ifier_lock);
284 /**************************************************/
285 /* af_can socket functions */
286 /**************************************************/
288 static void can_sock_destruct(struct sock *sk)
290 DBG("called for sock %p\n", sk);
292 skb_queue_purge(&sk->sk_receive_queue);
294 kfree(sk->sk_protinfo);
297 static int can_create(struct socket *sock, int protocol)
300 struct can_proto *cp;
303 DBG("socket %p, type %d, proto %d\n", sock, sock->type, protocol);
305 sock->state = SS_UNCONNECTED;
307 if (protocol < 0 || protocol >= CAN_NPROTO)
310 DBG("looking up proto %d in proto_tab[]\n", protocol);
312 /* try to load protocol module, when CONFIG_KMOD is defined */
313 if (!proto_tab[protocol]) {
314 char module_name[30];
315 sprintf(module_name, "can-proto-%d", protocol);
316 if (request_module(module_name) == -ENOSYS)
317 printk(KERN_INFO "af_can: request_module(%s) not implemented.\n",
321 /* check for success and correct type */
322 if (!(cp = proto_tab[protocol]) || cp->type != sock->type)
323 return -EPROTONOSUPPORT;
325 if (cp->capability >= 0 && !capable(cp->capability))
330 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,13)
331 sk = sk_alloc(PF_CAN, GFP_KERNEL, cp->prot, 1);
335 sk = sk_alloc(PF_CAN, GFP_KERNEL, 1, 0);
339 !(sk->sk_protinfo = kmalloc(cp->obj_size, GFP_KERNEL))) {
343 sk_set_owner(sk, proto_tab[protocol]->owner);
345 sock_init_data(sock, sk);
346 sk->sk_destruct = can_sock_destruct;
348 DBG("created sock: %p\n", sk);
351 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,13)
352 if (sk->sk_prot->init)
353 ret = sk->sk_prot->init(sk);
359 /* we must release sk */
371 static int can_notifier(struct notifier_block *nb,
372 unsigned long msg, void *data)
374 struct net_device *dev = (struct net_device *)data;
377 DBG("called for %s, msg = %lu\n", dev->name, msg);
380 if (dev->type != ARPHRD_CAN)
385 struct dev_rcv_lists *d;
388 case NETDEV_REGISTER:
390 /* create new dev_rcv_lists for this device */
392 DBG("creating new dev_rcv_lists for %s\n", dev->name);
393 if (!(d = kmalloc(sizeof(*d), GFP_KERNEL))) {
394 printk(KERN_ERR "CAN: allocation of receive list failed\n");
397 /* N.B. zeroing the struct is the correct initialization
398 for the embedded hlist_head structs.
399 Another list type, e.g. list_head, would require
400 explicit initialization. */
401 memset(d, 0, sizeof(*d));
404 spin_lock(&rcv_lists_lock);
405 hlist_add_head_rcu(&d->list, &rx_dev_list);
406 spin_unlock(&rcv_lists_lock);
410 case NETDEV_UNREGISTER:
411 spin_lock(&rcv_lists_lock);
413 if (!(d = find_dev_rcv_lists(dev))) {
414 printk(KERN_ERR "CAN: notifier: receive list not "
415 "found for dev %s\n", dev->name);
419 hlist_del_rcu(&d->list);
421 /* remove all receivers hooked at this netdevice */
422 can_rx_delete_all(&d->rx_err);
423 can_rx_delete_all(&d->rx_all);
424 can_rx_delete_all(&d->rx_fil);
425 can_rx_delete_all(&d->rx_inv);
426 can_rx_delete_all(&d->rx_eff);
427 for (i = 0; i < 2048; i++)
428 can_rx_delete_all(&d->rx_sff[i]);
431 spin_unlock(&rcv_lists_lock);
434 call_rcu(&d->rcu, can_rcv_lists_delete);
439 read_lock(¬ifier_lock);
440 list_for_each_entry (n, ¬ifier_list, list) {
442 n->func(msg, n->data);
444 read_unlock(¬ifier_lock);
449 static int can_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
451 struct sock *sk = sock->sk;
455 return sock_get_timestamp(sk, (struct timeval __user *)arg);
457 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,16)
460 return dev_ioctl(cmd, (void __user *)arg);
466 /**************************************************/
468 /**************************************************/
470 int can_send(struct sk_buff *skb, int loop)
474 if (loop) { /* local loopback (default) */
475 struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
476 newskb->protocol = htons(ETH_P_CAN);
477 newskb->ip_summed = CHECKSUM_UNNECESSARY;
478 *(struct sock **)newskb->cb = skb->sk; /* tx sock reference */
479 netif_rx(newskb); /* => local loopback */
482 if (!(skb->dev->flags & IFF_UP))
484 else if ((err = dev_queue_xmit(skb)) > 0) /* send to netdevice */
485 err = net_xmit_errno(err);
487 /* update statistics */
489 stats.tx_frames_delta++;
494 /**************************************************/
496 /**************************************************/
498 void can_rx_register(struct net_device *dev, canid_t can_id, canid_t mask,
499 void (*func)(struct sk_buff *, void *), void *data,
503 struct hlist_head *rl;
504 struct dev_rcv_lists *d;
506 DBG("dev %p, id %03X, mask %03X, callback %p, data %p, ident %s\n",
507 dev, can_id, mask, func, data, ident);
509 spin_lock(&rcv_lists_lock);
511 if (!(d = find_dev_rcv_lists(dev))) {
512 printk(KERN_ERR "CAN: receive list not found for "
513 "dev %s, id %03X, mask %03X\n", dev->name, can_id, mask);
517 if (!(rl = find_rcv_list(&can_id, &mask, d))) {
518 printk(KERN_ERR "CAN: receive list not found for "
519 "dev %s, id %03X, mask %03X, ident %s\n",
520 dev->name, can_id, mask, ident);
524 /* insert (dev,canid,mask) -> (func,data) */
525 if (!(r = kmem_cache_alloc(rcv_cache, GFP_KERNEL)))
535 hlist_add_head_rcu(&r->list, rl);
538 pstats.rcv_entries++;
539 if (pstats.rcv_entries_max < pstats.rcv_entries)
540 pstats.rcv_entries_max = pstats.rcv_entries;
543 spin_unlock(&rcv_lists_lock);
546 static void can_rcv_lists_delete(struct rcu_head *rp)
548 struct dev_rcv_lists *d = container_of(rp, struct dev_rcv_lists, rcu);
552 static void can_rx_delete(struct rcu_head *rp)
554 struct receiver *r = container_of(rp, struct receiver, rcu);
555 kmem_cache_free(rcv_cache, r);
558 static void can_rx_delete_all(struct hlist_head *rl)
561 struct hlist_node *n;
563 hlist_for_each_entry_rcu(r, n, rl, list) {
564 hlist_del_rcu(&r->list);
565 call_rcu(&r->rcu, can_rx_delete);
569 void can_rx_unregister(struct net_device *dev, canid_t can_id, canid_t mask,
570 void (*func)(struct sk_buff *, void *), void *data)
573 struct hlist_head *rl;
574 struct hlist_node *next;
575 struct dev_rcv_lists *d;
577 DBG("dev %p, id %03X, mask %03X, callback %p, data %p\n",
578 dev, can_id, mask, func, data);
582 spin_lock(&rcv_lists_lock);
584 if (!(d = find_dev_rcv_lists(dev))) {
585 printk(KERN_ERR "CAN: receive list not found for "
586 "dev %s, id %03X, mask %03X\n", dev->name, can_id, mask);
590 if (!(rl = find_rcv_list(&can_id, &mask, d))) {
591 printk(KERN_ERR "CAN: receive list not found for "
592 "dev %s, id %03X, mask %03X\n", dev->name, can_id, mask);
596 /* Search the receiver list for the item to delete. This must
597 * exist, since no receiver may be unregistered that hasn't
598 * been registered before.
601 hlist_for_each_entry(r, next, rl, list) {
602 if (r->can_id == can_id && r->mask == mask
603 && r->func == func && r->data == data)
607 /* Check for bug in CAN protocol implementations:
608 * If no matching list item was found, the list cursor variable next
609 * will be NULL, while r will point to the item of the list.
613 printk(KERN_ERR "CAN: receive list entry not found for "
614 "dev %s, id %03X, mask %03X\n", dev->name, can_id, mask);
619 hlist_del_rcu(&r->list);
622 if (pstats.rcv_entries > 0)
623 pstats.rcv_entries--;
626 spin_unlock(&rcv_lists_lock);
628 /* schedule the receiver item for deletion */
630 call_rcu(&r->rcu, can_rx_delete);
633 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,14)
634 static int can_rcv(struct sk_buff *skb, struct net_device *dev,
635 struct packet_type *pt, struct net_device *orig_dev)
637 static int can_rcv(struct sk_buff *skb, struct net_device *dev,
638 struct packet_type *pt)
641 struct dev_rcv_lists *d;
644 DBG("received skbuff on device %s, ptype %04x\n",
645 dev->name, ntohs(pt->type));
647 DBG_FRAME("af_can: can_rcv: received CAN frame",
648 (struct can_frame *)skb->data);
650 /* update statistics */
652 stats.rx_frames_delta++;
656 /* deliver the packet to sockets listening on all devices */
657 matches = can_rcv_filter(&rx_alldev_list, skb);
659 /* find receive list for this device */
660 if ((d = find_dev_rcv_lists(dev)))
661 matches += can_rcv_filter(d, skb);
665 /* free the skbuff allocated by the netdevice driver */
666 DBG("freeing skbuff %p\n", skb);
671 stats.matches_delta++;
678 static inline void deliver(struct sk_buff *skb, struct receiver *r)
680 struct sk_buff *clone = skb_clone(skb, GFP_ATOMIC);
681 DBG("skbuff %p cloned to %p\n", skb, clone);
683 r->func(clone, r->data);
684 r->matches++; /* update specific statistics */
688 static int can_rcv_filter(struct dev_rcv_lists *d, struct sk_buff *skb)
691 struct hlist_node *n;
693 struct can_frame *cf = (struct can_frame*)skb->data;
694 canid_t can_id = cf->can_id;
699 if (can_id & CAN_ERR_FLAG) {
700 /* check for error frame entries only */
701 hlist_for_each_entry_rcu(r, n, &d->rx_err, list) {
702 if (can_id & r->mask) {
703 DBG("match on rx_err skbuff %p\n", skb);
711 /* check for unfiltered entries */
712 hlist_for_each_entry_rcu(r, n, &d->rx_all, list) {
713 DBG("match on rx_all skbuff %p\n", skb);
718 /* check for can_id/mask entries */
719 hlist_for_each_entry_rcu(r, n, &d->rx_fil, list) {
720 if ((can_id & r->mask) == r->can_id) {
721 DBG("match on rx_fil skbuff %p\n", skb);
727 /* check for inverted can_id/mask entries */
728 hlist_for_each_entry_rcu(r, n, &d->rx_inv, list) {
729 if ((can_id & r->mask) != r->can_id) {
730 DBG("match on rx_inv skbuff %p\n", skb);
736 /* check CAN_ID specific entries */
737 if (can_id & CAN_EFF_FLAG) {
738 hlist_for_each_entry_rcu(r, n, &d->rx_eff, list) {
739 if (r->can_id == can_id) {
740 DBG("match on rx_eff skbuff %p\n", skb);
746 can_id &= CAN_SFF_MASK;
747 hlist_for_each_entry_rcu(r, n, &d->rx_sff[can_id], list) {
748 DBG("match on rx_sff skbuff %p\n", skb);
758 static struct dev_rcv_lists *find_dev_rcv_lists(struct net_device *dev)
760 struct dev_rcv_lists *d;
761 struct hlist_node *n;
763 /* find receive list for this device */
766 return &rx_alldev_list;
768 /* The hlist_for_each_entry*() macros curse through the list
769 * using the pointer variable n and set d to the containing
770 * struct in each list iteration. Therefore, after list
771 * iteration, d is unmodified when the list is empty, and it
772 * points to last list element, when the list is non-empty
773 * but no match in the loop body is found. I.e. d is *not*
774 * NULL when no match is found. We can, however, use the
775 * cursor variable n to decide if a match was found.
778 hlist_for_each_entry(d, n, &rx_dev_list, list)
785 static struct hlist_head *find_rcv_list(canid_t *can_id, canid_t *mask,
786 struct dev_rcv_lists *d)
788 canid_t inv = *can_id & CAN_INV_FILTER; /* save flag before masking values */
789 canid_t eff = *can_id & *mask & CAN_EFF_FLAG; /* correct EFF check? */
790 canid_t rtr = *can_id & *mask & CAN_RTR_FLAG; /* correct RTR check? */
791 canid_t err = *mask & CAN_ERR_FLAG; /* mask for error frames only */
793 /* make some paranoic operations */
794 if (*can_id & CAN_EFF_FLAG)
795 *mask &= (CAN_EFF_MASK | eff | rtr);
797 *mask &= (CAN_SFF_MASK | rtr);
801 if (err) /* error frames */
804 if (inv) /* inverse can_id/can_mask filter and RTR */
807 if (*can_id & CAN_RTR_FLAG) /* positive filter RTR */
810 if (!(*mask)) /* mask == 0 => no filter */
813 if (*can_id & CAN_EFF_FLAG) {
814 if (*mask == CAN_EFF_MASK) /* filter exact EFF can_id */
817 if (*mask == CAN_SFF_MASK) /* filter exact SFF can_id */
818 return &d->rx_sff[*can_id];
821 return &d->rx_fil; /* filter via can_id/can_mask */
824 /**************************************************/
825 /* af_can utility stuff */
826 /**************************************************/
828 unsigned long timeval2jiffies(struct timeval *tv, int round_up)
831 unsigned long sec = tv->tv_sec;
832 unsigned long usec = tv->tv_usec;
834 if (sec > ULONG_MAX / HZ) /* check for overflow */
837 if (round_up) /* any usec below one HZ? */
838 usec += 1000000 / HZ - 1; /* pump it up */
840 jif = usec / (1000000 / HZ);
842 if (sec * HZ > ULONG_MAX - jif) /* check for overflow */
845 return jif + sec * HZ;
849 /**************************************************/
850 /* af_can debugging stuff */
851 /**************************************************/
853 #ifdef CONFIG_CAN_DEBUG_CORE
855 void can_debug_cframe(const char *msg, struct can_frame *cf, ...)
862 len = sprintf(buf, KERN_DEBUG);
864 len += snprintf(buf + len, sizeof(buf) - 64, msg, ap);
869 if ((dlc = cf->can_dlc) > 8)
872 if (cf->can_id & CAN_EFF_FLAG)
873 len += sprintf(buf + len, "<%08X> [%X] ",
874 cf->can_id & CAN_EFF_MASK, dlc);
876 len += sprintf(buf + len, "<%03X> [%X] ",
877 cf->can_id & CAN_SFF_MASK, dlc);
879 for (i = 0; i < dlc; i++)
880 len += sprintf(buf + len, "%02X ", cf->data[i]);
882 if (cf->can_id & CAN_RTR_FLAG)
883 len += sprintf(buf + len, "(RTR)");
890 void can_debug_skb(struct sk_buff *skb)
896 KERN_DEBUG " skbuff at %p, dev: %d, proto: %04x\n"
897 KERN_DEBUG " users: %d, dataref: %d, nr_frags: %d, "
898 "h,d,t,e,l: %p %+d %+d %+d, %d",
899 skb, skb->dev ? skb->dev->ifindex : -1,
900 ntohs(skb->protocol),
901 atomic_read(&skb->users),
902 atomic_read(&(skb_shinfo(skb)->dataref)),
903 skb_shinfo(skb)->nr_frags,
904 skb->head, skb->data - skb->head,
905 skb->tail - skb->head, skb->end - skb->head, skb->len);
906 nbytes = skb->end - skb->head;
907 for (i = 0; i < nbytes; i++) {
909 len += sprintf(buf + len, "\n" KERN_DEBUG " ");
910 if (len < sizeof(buf) - 16) {
911 len += sprintf(buf + len, " %02x", skb->head[i]);
913 len += sprintf(buf + len, "...");
922 EXPORT_SYMBOL(can_debug_cframe);
923 EXPORT_SYMBOL(can_debug_skb);
927 /**************************************************/
928 /* Exported symbols */
929 /**************************************************/
930 EXPORT_SYMBOL(can_proto_register);
931 EXPORT_SYMBOL(can_proto_unregister);
932 EXPORT_SYMBOL(can_rx_register);
933 EXPORT_SYMBOL(can_rx_unregister);
934 EXPORT_SYMBOL(can_dev_register);
935 EXPORT_SYMBOL(can_dev_unregister);
936 EXPORT_SYMBOL(can_send);
937 EXPORT_SYMBOL(timeval2jiffies);